The Sun
The Sun is a yellow dwarf star (G2V), about 4.6 billion years old, and the dominant gravitational force in the Solar System. It has a diameter of roughly 1.4 million kilometers and contains around 99.8% of the Solar System’s mass. Nuclear fusion in its core converts hydrogen into helium, producing energy that warms the planets. Above the core lie the radiative and convective zones, followed by the visible photosphere (~5,500 °C), the chromosphere, and the much hotter corona (~2 million °C).
Source: science.nasa.gov
APODs including "The Sun"
Galaxy Cluster Abell S1063 and Beyond
22/07/2016
Some 4 billion light-years away, galaxies of massive Abell S1063 cluster near the center of this sharp Hubble Space Telescope snapshot. But the fainter bluish arcs are magnified images of galaxies that lie far beyond Abell S1063. About twice as distant, their otherwise undetected light is magnified and distorted by the cluster's largely unseen gravitational mass, approximately 100 trillion times the mass of the Sun. Providing a tantalizing glimpse of galaxies in the early universe, the effect is known as gravitational lensing. A consequence of warped spacetime it was first predicted by Einstein a century ago. The Hubble image is part of the Frontier Fields program to explore the Final Frontier.